code: def __len__(self):
      if self.is_eval:
          return len(self.samples)
      return sum([len(v) for v in self.samples.values()])
  
file_path: TTS/TTS/tts/layers/xtts/trainer/dataset.py
imports: import os
  import random
  import sys
  import torch
  import torch.nn.functional
  import torch.utils.data
  from TTS.tts.models.xtts import load_audio
label_desc: Use image node_id 6 for calling the XTTSDataset obj's underlying member method code with example usage: obj.__len__() and returns: sum, len